The first layer of the aura is considered to be the skin, and is connected to the feelings associated to the first chakra - survival and identity. It is "THE ETHERIC BODY", it's varies from light blue to grey and it's the easiest layer to see when you start seeing auras.
The second layer of the aura follows more or less the contour of the body and is associated to "feeling ok" and what feels right and wrong: When this layer is in good conditions, we feel happy and content. It is "THE EMOTIONAL BODY".
The third layer is generally called "THE MENTAL BODY", it relates to the third chakra and looks like a wire mesh. It is generally yellowish, but can have cultural variations. Cyndi Dale says:
The fourth auric layer is "THE ASTRAL BODY". It corresponds to the heart chakra. When this layer opens, it makes us exprerience astral projection.Many Caucasian American, northern European, and Jewish cultures appear to have a predominantly yellow third auric layer. Yellow is thr color of rationality, thinking and clarity, attributes of value to these nationalities. The mind field in several Indian and Pakistani nations has a bluish or sometimes purplish tinge. In Peru, the shamans I met glowed with bright reds and greens. While watching North American Indian ceremonies, I detected more turquoise, gold, white, or muddy red, depending on the tribes. In all cases, shades of these colours lingered long afterwards. In Japan, I detected particles of silver. Different ethnic groups, different cultures probably tap into different points of consciousness in the group mind.
The fifth auric field is called sometimes "the parallel field". It connects us to parallel opportunities and realities, and allows us to receive information and healing energy. This is "THE ETHERIC TEMPLATE". It's a blueprint for the etheric layer.
The sixth auric field is "THE CELESTIAL BODY". It allows psychic manifesting and healing.
The seventh auric field is considered to be the last layer around our physical body, it is "THE KETHERIC BODY".
The eight auric field is related to the eighth chakra and it is the layer where the Akashic Records are to be found.
The ninth auric field is connected to a state of bliss and enlightment - heaven, nirvana or Shamballa.
There is also another field that is connected to the tenth chakra and that is the Integrative Auric Layer.
The first three layers are part of the physical plane, the fourth/astral layer is a bridge to the higher spiritual planes, layer five, six and seven.
I shall examine some of these ten layers as they are fairly interesting and I may as well integrate more info in this message little by little so come back to it from time to time! It is by no means complete...
There may also be other auric layers, and that is under current study.